In September, 2003, Wizards of the Coast (makers of the Magic: The Gathering
and Pokemon collectible card games) released The Simpsons Trading Card
Game. (For those of you unfamiliar with the term, a "trading card game" is
a game where each player plays against the others with their own deck of cards,
usually constructed from purchased "starter" and "booster" packs. Some cards are
rarer than others, so you are expected to trade some of your cards for the cards
that you want to make what you think will be the best deck of 40 cards, hence
"trading card game". The term "collectible card game" means the same thing,
although the term usually applies when the cards have a collector's value as
well...then again, all of the rare cards, except for the "star" cards, have both
foil and regular versions, which are the same as far as game play is concerned,
so there is some collectibility involved.)

The object of the game is to score points by assigning characters to scenes from
the show. There are three kinds of cards:

Scene cards, which depcit a scene such as "Krusty Burger". Each scene
(with a few exceptions) has a "complete" value and a "trash" value, as well as a
number of character traits and a special feature.

Character cards, which depict a character such as "Jasper". Each
character has a list of traits. Character cards are played onto scene cards
in order to "complete" or "trash" the scene.

Action cards, which let a player perform a certain action or affects
all of the players somehow. Some can be played at any time, while others can
only be played at certain times (usually during the player's turn). For example,
"Kid Stuff" can be played during a player's turn; it causes all Characters in play
without the "Kid" trait to be discarded.

The object is to play a scene card, then to play characters onto scenes
(both your own and others) in order to score points. You may only have one
scene in play at any one time, and cannot remove it until it has been either
completed or trashed. A scene may be "completed" when the number of character
cards on the scene that have at least one of the scene's traits on it is greater
than or equal to the scene's completion value, and may be "trashed" when the
number of character cards on the scene that have none of the scene's traits on it
is greater than or equal to the scene's trash value. Note that a scene does not
have to be declared completed or trashed at the first opportunity, and that any
player may declare a scene completed or trashed on their turn if it has enough of
the appropriate cards.
For example, a player plays the scene Krustylu Studios, which has a completion
value of 5, a trash value of 4, the traits Idiot and Celebrity, and the feature
that if it is completed using Krusty, whoever played the scene gets one extra
point. The character Poochie has the traits Oddball, Idiot, Cartoon, and
Animal; Idiot is one of the scene's traits, so Poochie counts toward the scene's
completion value. The character Comic Book Guy has the traits Fat, Brainy,
Bitter, and Oddball, none of which are either of the scene's traits, so Comic
Book Guy counts towards the scene's trash value. Note that not all of the
played cards have to match the same trait (for example, Krustylu Studios can
be completed with three Bleeding Gums Murphy cards, which have Celebrity but not
Idiot, and two Lenny cards, which have Idiot but not Celebrity), nor do all of
the traits on the scene have to be present (the scene can be completed with
two Bartmans, two Dr. Marvin Monroes, and one Brad Goodman, none of which have
Idiot). There is also no limit on how many of each card can be played at any
one time.
When a scene is completed or trashed, the player who placed the scene in the
first place scores a point, and all other players who have played at least
one character counted toward the completion or trash score a point (regardless
of the number of cards played, and note that the player who placed the scene
does not also score for having characters on it). In addition, if a scene is
completed (but not trashed) and one player (including the player who placed the
scene) has more counting characters than any other player, this player scores
an additional point. The game ends when someone has seven or more points (or
has six and plays the "Game Over" action); whoever has the most points wins.
If there is a tie, then, in the words of Troy McClure, "they're all winners"
(that's from "A Streetcar Named Marge"...and I don't remember anything wrong
with there being a "tie" in "Lisa on Ice").
What's meant by a "counting character"? Well, remember when I said that you
do not have to declare a scene completed or trashed as soon as there are
enough cards? This is because if there are more completion/trash cards than
the scene's completion/trash value, whoever declared the scene completed/trashed
selects which cards are counted, just as long as the player counts at least as
many cards as the completion/trash value. (Obviously, if it's a completion,
the player would want to count all of that player's own cards, in order to try
to get the bonus point.)

Here is the list of cards, at least in the original starter and booster sets.
There are four starter decks in the original set, each with 40 cards: Homer,
Bart, Lisa, and Mr. Burns. (All Homer decks, for example, contain the same 40
cards.) Each booster pack contains 11 cards, none of which are in any of the
starter decks.

* indicates a rare card; all rare cards have foil as well as regular versions,
except for the Star Cards, which only have foil versions.
All other cards are "common" cards, and do not have foil versions. (There is no
third level of rarity, like the "Uncommon" level of Magic: the Gathering.)
Letters indicate cards in the starter decks: (B)art, (H)omer, (L)isa, (M)r. Burns.
Each common character or action card in a starter deck appears three times; each
common scene card in a starter deck appears twice; each rare card in a starter
deck appears once. (There are three different Marge Simpson and three different
Maggie Simpson cards; one of each Marge card appears in the Homer deck, and one
of each Maggie card appears in the Lisa deck.)

Either somebody knew in advance that Dr. Marvin Monroe was still alive after
all, they didn't get the memo that Dr. Marvin Monroe was (supposedly) dead,
or they forgot to include Maude Flanders. (Also notice that for whatever reason,
the only character not in anything resembling alphabetical order is Helen Lovejoy.)
Speaking of forgetting, while they managed to find room for one-time characters
like Mojo the Helper Monkey and (Stonecutter) Number One, there are no cards for
regulars like Miss Hoover or Sanjay. (It's possible that there could be an
expansion set in the future, but there don't seem to be that many characters left
out to make it feasible.)

Note that some traits, like "Duo", appear on multiple cards but not on any
scenes; however, the action cards "Guilt by Association", "Losers Pay", and
"Wipe Out" can affect cards of any selected trait.

Until Wizards of the Coast comes up with some additional rule clarifications,
here are some I thought of:

If a scene says "If this scene is completed using ______" (for example,
Bart in Bart's Treehouse), that character does not have to be the last card
played on the scene before it is declared completed; however, it must be one
of the cards chosen to complete the scene.

All points for completing or trashing a scene are scored simultaneously.
Interpret the "Share the Wealth" action card as saying, "If you otherwise would
not have received any points, you get 1 point."

Once a player has seven or more points, no more action cards (such as
"Knocked Down a Peg" or "Game Over") may be played.

Despite Old being listed three times on his card, each Hans Moleman card
counts as one character at all times.